This invention relates to an improved video film projector having a pin registration transport mechanism and a synchronizing shutter. Pin registration transport of a film strip is well known and comprises a small angled pin disposed in the gate of a projector to engage respective perforations in the edge of the film as it moves through the gate. The film strip is driven on both sides of the gate. After passing through the gate and over the registration pin, the film is looped around whereby driving of the film downstream of the gate will tend to pull it off the pin. Driving of the film upstream of the gate forms a loop whereby when the film is pulled off the pin will be advanced through the gate by the inherent spring tension of the upstream loop.
Although shuttering mechanisms have been provided in the past for pin registration transport systems, the prior art has not provided a means to synchronize the shutter and film transport at very slow, variable frame-per-second speeds.
This invention also relates to self-threading motion picture projectors which employ film storage cartridges which are adapted to snap onto appropriate mounting means on the projector whereby the film will be aligned for moving through the gate of the projector. In the past such cartridges have not been provided with satisfactory means for retaining the leading end of the film strip in proper orientation for feeding into the gate upon mounting of the cartridge on the projector. When such film is rewound, the leading end of the film is rewound into the cartridge whereupon it must be "fished" out of the cartridge prior to the next showing of the film. Such drawbacks are avoided by use of one endless loop cassette. However, professional equipment and experience are required to properly load film in such a cassette, making the use of such cassettes impracticable for homemovie use where it is desired to edit and splice film strips together.
This invention also relates to projector film take-up and rewind mechanisms.